Small Engines (Lawn Mowers, etc.): Briggs and Statton 18.5 verticle problem, briggs and statton, jumper wire

Question
Can't get my lawn mower to start. If I take the plugs out it will crank but when you put the plugs back in it won't even turn
                                Thanks

Answer
Hi George,

I suspect a weak battery.  Follow my No Cranking procedure below, using what applies.

Let me know how you make out.
Michael

I would check the starter first.  Jump the positive battery terminal to the starter and it should crank over. If so, skip to step 2. If not, jump from a battery that you know is good, from a car.  If still nothing, the starter is bad.  If good, then the mower battery is weak.  

Step 2.
If the starter and battery are good, you will need to trace the entire circuit from the starter to the battery.   The solenoid, switches the battery power to
the starter, when power from the key switch is sent to the small terminal on the solenoid. To test the solenoid, first make sure that you have power at its large
terminal which comes from the battery. Then jump power from that terminal or the battery positive post, to its small terminal. You should hear a click and the
other large terminal that feeds the starter should be energized. If not, then the solenoid is bad. If good, then continue tracing the power through the key
switch to the battery until you find the break in the power path.   All testing can be done with a 12 volt light or a voltmeter.  Most equipment has safety
switches in  the seat and on the blade engagement lever. Check them by temporarily bypassing with a small jumper wire.